Last night I couldn't unlock my phone, and I couldn't press the 'back' arrow to get out of the 'press the unlock key' thing, so I took the battery out and restarted it and when it was on again, the keys were all messed up ie: 'end' gives me 'U', 'space' brings up the symbols list, and all other letters bring give me several letters at once ie: 'c' = 'ct' etc. I'm switching carriers in a month or so and don't want to buy a new phone. Please help me fix this problem. Thank you!

It does, indeed. Pull the battery out and look at the moisture sensor in the battery compartment. (It's the small square thingy next to the battery contacts on the inside of the phone.) What color is it?